Keys and MOI - wipp assist

Richard Brekne Richard.Brekne@grieg.uib.no
Wed, 07 Jan 2004 03:13:45 +0100


John Hartman wrote:
> 
> Let's say we have an action with a wip spring.
> it is set up so there is a balance weight of 45 gm when the spring is
> not attached. When the spring is attached the balance weight goes down
> to 35 gm. The force that just begins to move the key will be:
> 
> 45*980gm/sec^2 - 10*908gm/sec^2

Grams per second squared ?? Not exactly sure what you are saying here...
beyond the fact that the existing BW (plus a hair) represents the flip
side of the force needed to get things moving. Would you clarify this a
bit please ?

> 
> After this force is applied to the key any additional force used to move
> the action will answer to the the inertia of the rotating parts
> (assuming there is no friction or other factors).

Yep


> 
> John Hartman RPT
> 
RicB

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